Method and apparatus for providing fraud protection mediation in a mobile telephone system

ABSTRACT

The system and method of the present invention facilitates an improved home location register (HLR) that includes a fraud protection mediation module for use in a mobile telephone system. The fraud protection mediation module operates in any one of the following situations: (1) a registration notice (REGNOT) is received by the HLR from a mobile switching center (MSC) currently serving a subscriber in a roaming area; (2) a qualification request (QUALREQ) is received by the HLR from a serving MSC for obtaining a subscriber&#39;s profile; and (3) the HLR sends a qualification directive to a serving MSC, with the updated or modified profile of the subscriber. By using the improved HLR of the present invention, a carrier may have the HLR bypass the fraud protection processing in areas that support authentication processing to provide convenience to the subscribers so that they do not have to enter their PINs to use their cellular phones. Alternatively, if authentication processing is available, the cellular carrier may use fraud protection processing as a backup protection measure.

RELATED APPLICATIONS

The following applications are related to the subject application. Eachof the following applications is incorporated by reference herein.

1. U.S. application Ser. No. 08/781,262 entitled "Method and Apparatusfor Providing Switch Capability Mediation in a Mobile Telephone System,"of Lamb et al., filed Jan. 11, 1997;

2. U.S. application Ser. No. 08/781,259 entitled "Method and Apparatusfor Implementing Alias Mobile ID Numbers in a Mobile Telephone System,"of Lamb, filed Jan. 11, 1997;

3. U.S. application Ser. No. 08/781,261 entitled "Method and Apparatusfor Implementing Configurable Call Forwarding Bins in a Mobile TelephoneSystem," of Lamb, filed Jan. 11, 1997;

4. U.S. application Ser. No. 08/781,260 entitled "Method and Apparatusfor Method and Apparatus For Automated Updates on an A-Key Entry In aMobile Telephone System," of Jacobs, filed Jan. 11, 1997;

5. U.S. application Ser. No. 08/780,830 entitled "Method and Apparatusfor Configuration of Authentication Center Operations Allowed by MSCIDin a Mobile Telephone System," of Jacobs et al., filed Jan. 11, 1997;

6. U.S. application Ser. No. 08/781,258 entitled "Method and Apparatusfor Configuration of Authentication Center Operations Allowed by SystemAccess Type in a Mobile Telephone System," of Jacobs, filed Jan. 11,1997;

7. U.S. application Ser. No. 08/781,263 entitled "Method and Apparatusfor Authentication Directive initiation Limits in a Mobile TelephoneSystem," of Jacobs, filed Jan. 11, 1997.

BACKGROUND OF THE INVENTION

The invention generally relates to a wireless communication network, andmore particularly, relates to an improved home location register (HLR)that provides fraud protection mediation in a wireless communicationnetwork.

Wireless communication is one of the fastest growing segments of thetelecommunication industry. With the mobility of the wireless devices,such as cellular phones and pagers, a subscriber to a wireless servicecan make or receive a call or receive a message without being restrictedto any particular locations. Because of the convenience provided bywireless devices, they have been widely used by average consumers.

Wireless communications are provided through a wireless communicationnetwork, which can be realized, for example, as a Signaling System 7(SS7) network. The SS7 network uses the EIA/TIA Interim Standard 41(IS-41) protocol, which is the standard commonly used in North America.A description of the SS7 network and the IS-41 protocol can be found inSignaling System #7, by Travis Russell, and The Mobile CommunicationsHandbook, by Jerry Gibson, which are hereby incorporated by reference.

The SS7 network is used for switching data messages pertaining toconnecting telephone calls and for maintaining the signaling network. Asshown in FIG. 1, the SS7 network 100 has three different types of nodesor signaling points: Service Switching Point (SSP) 112, Signal TransferPoint (STP) 116, and Service Control Point (SCP) 122.

An SSP 112 is a local exchange in the telephone network. An SSP 112 usesthe information provided by the calling party (such as dialed digits)and determines how to connect the call. An STP 116 serves as a router inthe SS7 network and switches SS7 messages as received from the variousSSPs 112 through the network to their appropriate destinations. An STP116 receives messages in packet form from an SSP 112. These packets areeither related to call connections or database queries for an SCP 122.If the packet is a request from an SSP 112 to connect a call, themessage must be forwarded to the destination where the call will beterminated. The destination is determined by the dialed digits. If themessage is a database query seeking additional information regarding aperson who subscribes a wireless service, i.e., a "subscriber", thedestination will be a database. Access to telephone company databases isprovided through an SCP 122. These databases are used to storeinformation about subscribers' services, calling card validation, fraudprotection, etc.

As shown in FIG. 1, the wireless network is shared by multiple regions126, such as regions A and B. In each region 126, an SCP 122 isprovided. Each region 126 is further divided into a number ofregistration areas 132, each of which is served by a Mobile SwitchingCenter (MSC) 136. An MSC 136 provides wireless communication services toall properly registered cellular phones 142 in the registration area.

As illustrated in FIG. 1, an SCP 122 contains an authentication center(AC) 146 and a home location registers (HLR) 152. AC 146 authenticates asubscriber's cellular phone through the use of an encrypted numbercalled the A-Key. HLR 152 is used to store information regardingcellular subscribers in the region for which it provides services. HLR152 also stores information identifying the services allowed for eachsubscriber. In addition to these, HLR 152 stores the current locationsof cellular phones 142 of those subscriber's who initially activatedtheir cellular phones through a wireless service provider in the regionthe HLR serves. This region is also referred to as the "home area" ofthose subscribers. Although not shown, a backup HLR is also provided inSCP 122.

A visitor location register (VLR) 156 is also provided in each region126. VLR 156 is used when a cellular phone 142 is not recognized by alocal MSC. VLR 156 stores the current locations for the visitingsubscribers.

With the unparalleled growth of wireless communications services hascome an equally noteworthy but unfortunate trend. Cellular fraud--thetheft of cellular airtime by criminals employing a variety ofmethods--has become an enormous business challenge for cellular carriersand a nuisance for legitimate cellular subscribers. In the United Statesalone, industry estimates of lost revenue attributed to unauthorized useof cellular networks range from US$1 million to close to US$3 millionper day. Carriers' ability to detect cellular fraud, manage it, and tothe extend they can, prevent it has become critical to sustaining bothprofitability and competitive advantage.

HLR-based fraud protection feature has been implemented by automaticallylocking cellular phones when they are inactive. This preventsunauthorized use of a subscriber's phone and/or fraudulent access to thenetwork by cloned phones. When a subscriber initially registers with thenetwork, the HLR requires the subscriber to enter a feature code andpersonal identification number (PIN) before access is granted. Thesubscriber can then lock the phone again by entering the same featurecode and PIN. If an unlocked phone becomes inactive for a predeterminedperiod of time, the HLR automatically invokes the fraud protectionfeature until the subscriber unlocks the phone with feature code and PINentries. This feature prevents access to the network by a cloned phoneusing the valid subscriber's MIN (Mobile ID Number) or ESN (EquipmentSerial Number) while the valid subscriber is inactive.

However, in areas where authentication processing operates toauthenticate cellular phones, it may not be necessary to operate fraudprotection processing which requires a subscriber to enter a PIN tounlock his cellular phone for accessing the network. To provideconvenience to subscribers so that they do not have to enter their PINsto use their phones, fraud protection processing should be operated inareas where authentication processing is not available.

Accordingly, fraud protection mediation is needed in different areasthat support either authentication processing or fraud protectionprocessing, or both. This will provide great convenience to subscribersin those areas where authentication processing is performed on cellularphones.

SUMMARY OF THE INVENTION

The present invention provides an improved home location register (HLR)that includes a fraud protection mediation module for use in a mobiletelephone system. According to the invention, the fraud protectionmediation module operates in any one of the following situations: (1) aregistration notice (REGNOT) is received by the HLR from an MSCcurrently serving a subscriber in a roaming area; (2) a qualificationrequest (QUALREQ) is received by the HLR from a serving MSC forobtaining a subscriber's profile; and (3) the HLR sends a qualificationdirective to a serving MSC, with the updated or modified profile of thesubscriber. When any of the above situations occurs, the mediationmodule reads in the HLR the MPCM (MSC ID Point Code Map File) record ofthe serving MSC to determine whether the area this serving MSC servessupports authentication processing and whether the MSC is fraud capable(i.e., whether the MSC supports fraud protection processing). Then, themediation module reads the subscriber's profile record in the SUBS fileof the HLR to determine if the subscriber has an active authenticationand has fraud protection authorized. Next, the mediation moduledetermines whether the fraud protection bypass feature is activated forthis HLR. Based on this various information, the mediation modulesrefers to an AC/FP lookup table to determine the appropriate check orchecks that are needed for the subscriber's cellular phone. Themediation module then sends an appropriate request to the conventionalcomponents of the HLR for performing the check or checks.

By using the improved HLR of the invention, a carrier may have the HLRbypass the fraud protection processing in areas that supportauthentication processing to provide convenience to the subscribers sothat they do not have to enter their PINs to use their cellular phones.Alternatively, if authentication processing is available, the cellularcarrier may use fraud protection processing as a backup protectionmeasure.

Other objects and attainments together with a fuller understanding ofthe invention will become apparent and appreciated by referring to thefollowing description and claims taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a typical SS7 mobile communication network;

FIG. 2 shows an example of an HLR according to the invention;

FIG. 3 shows an MPCM file record of an MSC according to the invention;

FIG. 4 shows a partial format of a subscriber's profile in a SUBS fileof an HLR according to the invention;

FIG. 5 shows an example of an SYSP file of an HLR according to theinvention;

FIG. 6 shows an AC/FP lookup table according to the invention;

FIG. 7 shows a flow diagram illustrating a registration process and calldelivery when the receiving party's cellular phone is outside its homearea in a roaming area; and

FIG. 8 shows a flow chart of the fraud protection mediation moduleaccording to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 2 shows home location register (HLR) 200 according to theinvention. As shown, HLR 200 includes at least conventional HLRcomponents 212, MPCM file 216, SUBS file 222, SYSP file 224, SPCD file225, AC/FP lookup table 226 and fraud protection mediation module 228.

MPCM file 216 is the "MSC ID Point Code Map File" which store MSCs'network configuration information. Each MSC communicating to an HLR hasa corresponding MPCM file record in the MPCM file of the HLR. SUBS file222 is the "subscribers' files" which store subscribers' profiles on aper subscriber basis (i.e, information for each cellular phone). Usuallyone SUBS file in the HLR contains information about all of its homesubscribers (i.e., the subscribers who initially activated theircellular phones in the region the HLR serves). SYSP file 224 is the"System Parameters File" which stores global information about how thesystem should operate. SPCD file 225 is the "Serving Point Code File"which stores the network addresses in the form of point codes forvarious network components including MSCs. AC/FP lookup table 226contains information about what fraud protection related process orprocesses should be performed for any particular subscriber undervarious conditions. Fraud protection mediation module 228 is anapplication program that implements fraud protection mediation for aparticular subscriber in accordance with AC/FP lookup table 226. It willbe understood by persons of ordinary skill in the art that functionsperformed by the HLR are implemented by a processor executing computerinstructions stored in a memory.

FIG. 3 illustrates a partial format of an MPCM file record associatedwith an MSC in MPCM file 216. This file record includes a number offields. Some of the relevant fields are described below. The MSCID₋₋ KEYfield identifies this MSC's ID (MSCID) number. It is the primary key tothe MPCM files. The POINT₋₋ CODE₋₋ SSN field identifies the network IDand subsystem (SSN), etc. for this MSC. The HLR₋₋ SSN field stores thevalue the HLR will use as the SSN when communicating with this MSC. TheIS-41 revision level of this MSC, e.g., IS-41 Rev A, IS-41 Rev B, etc,is stored in the REV₋₋ LEVEL field. Moreover, the vendor of this MSC,e.g., AT&T, Ericsson, Motorola, or Northern Telecom, etc. is identifiedby SWITCH₋₋ VENDOR field. The OPT7₋₋ IND field indicates whether theVisitor Location Register (VLR) serving this MSC can perform anauthentication (AC) check. The OPT12₋₋ IND field indicates whether thisMSC is fraud-capable, i.e., whether the HLR can perform a fraudprotection (FP) check to a subscriber in the registration area this MSCserves. The FP check requires a subscriber to unlock the phone when thesubscriber wants to place a call. The AC and FP checks may be performedfor example, through the AC and FP processing software TSCP-AC andTSCP-HLR respectively, both of which are developed by Tandem Telecom inOmaha, Neb.

FIG. 4 shows a partial format of a subscriber's profile record in SUBSfile 222. There are several segments in each subscriber's profilerecord, including the BASE₋₋ REC₋₋ INFO, SHARED₋₋ INFO, TRANSIENT₋₋INFO, etc. Each segment includes multiple fields. The BASE₋₋ REC₋₋ INFOsegment contains information needed by IS-41 applications to access asubscriber record. This segment includes the R₋₋ MIN₋₋ KEY, ESN fields,etc. The R₋₋ MIN₋₋ KEY field is the subscriber file's primary key. Itcontains the subscriber's MIN (Mobile ID number) stored in reverse byteorder. The ESN field is the subscriber file's alternate key. It containsthe Equipment Serial Number (ESN) associated with the subscriber's MIN.

The SHARED₋₋ INFO segment of a subscriber's profile record storesattributes common to the IS-41 applications. This segment includes theHOME₋₋ MSCID, SHARED₋₋ ACCESS₋₋ MAP, AUTH₋₋ ENABLED fields, etc. TheHOME₋₋ MSCID field identifies the ID number of the MSC that is in thesubscriber's home area where the subscriber initially activates hiscellular phone. The SHARED₋₋ ACCESS₋₋ MAP field is a bitmap identifyingthe IS-41 applications currently accessing the subscriber's data. TheAUTH₋₋ ENABLED field identifies whether or not authentication is enabledand should be performed for this subscriber.

The TRANSIENT₋₋ INFO segment of a subscriber's profile record stores theregistration information about this subscriber. This segment includesthe VLR₋₋ MSCID, REG₋₋ STATUS₋₋ IND fields, etc. The VLR₋₋ MSCID fieldidentifies the MSCID of the VLR in a roaming area where the subscriberis currently registered. The REG₋₋ STATUS₋₋ IND field identifies thesubscriber's registration status. This field stores the informationrelating to, e.g., whether the subscriber is registered, whetherregistration is active in the home area, and whether the registration isactive in the roaming area.

The FRAUD₋₋ INFO segment of a subscriber's profile record indicateswhether or not fraud protection (i.e., FP check) is authorized for thissubscriber. The PIN₋₋ INFO segment stores the subscriber's personalidentification number (PIN).

FIG. 5 shows a partial format of SYSP file 224 of the HLR. The BYPASS₋₋FP field indicates whether the fraud protection bypass feature isactivated for this HLR. If this feature is activated, then no FP checkwill be performed by this HLR when authentication processing isavailable.

FIG. 6 shows AC/FP look up table 226 of the HLR. This table isreferenced for determining whether an AC check or an FP check or bothchecks are needed in each of the 16 cases identified by the case field.The fp-act field indicates whether the fraud protection for a particularsubscriber is authorized. The information is stored in the FRAUD₋₋ INFOfield of the subscriber's profile record in the SUBS file. The can-isacfield is determined based on the information of whether the subscriberhas an active authentication and whether the area the subscriber is insupports AC processing. If any one of the two conditions is not true,the can-isac is inactive and stores a zero. The can-isac is active andstores 1, only when both the subscriber has an active authentication andthe area the subscriber is in supports AC processing. The information ofwhether the subscriber has an active authentication is stored in theAUTH₋₋ ENABLED field of the subscriber's profile record in the SUBSfile. The information about whether the area supports AC processing isstored in the OPT7₋₋ IND field of the MPCM file record associated withan MSC currently serving the subscriber. The can-fp field identifieswhether the serving MSC is fraud capable. This information is stored inthe OPT12₋₋ IND field of the MPCM file record of the serving MSC. Thebypass-fp indicates whether the fraud protection bypass feature isactivated for this HLR. This information is stored in the BYPASS₋₋ FPfield in the HLR's SYSP file. Finally, the isac field indicates whetheran AC check should be performed on this subscriber's cellular phone; andthe fp field indicates whether an FP check should be performed on thissubscriber's cellular phone.

As shown in this lookup table, if the can-isac is inactive, i.e., eitherthe subscriber does not have an active authentication or the area thesubscriber is in does not support AC processing, as in cases 1-4 and9-12, then an AC check will not be performed. In these cases, however,if the fraud protection is authorized (i.e., the fp-act is active) andthe MSC is fraud capable (i.e., the can-fp is active), as in cases 11and 12, then an FP check will be performed regardless of whether thebypass-fp is active or inactive (i.e., regardless of whether the fraudprotection bypass feature is activated or not). However, if the can-isacis active, i.e., the subscriber has an active authentication and thearea the subscriber is in supports AC processing, as in cases 5-8 and13-16, then an AC check will always be performed. In these cases, if thefraud protection is also authorized (i.e., the fp-act is active) and theserving MSC is fraud capable (i.e., the can-fp is active), as in cases15 and 16, then an FP check will be performed only if the bypass-fp isinactive as in case 15. If the bypass-fp is active, as in case 16, thenan FP check will be bypassed and only an AC check will be performed. Inthis way, an AC check is performed whenever the subscriber has an activeauthentication and the area the subscriber is in supports AC processing.An FP check may be used as a backup protection. Alternatively, acellular carrier may bypass the FP check in areas that support ACprocessing to provide convenience to the subscribers so that they do nothave to enter their PINs to use their cellular phones.

The present invention can be best understood by the working exampledescribed below.

FIG. 7 illustrates how call delivery is made to a cellular phone that isoutside its home area 612 in a roaming area 616. Home area 612 androaming area 616 correspond to two regions, such as regions A and B,respectively, shown in FIG. 1. In home area 612, an SCP 622 and a VLR642 are provided. SCP 622 includes an AC 632 and an HLR 636. A home MSC643 is located in home area 612. In roaming area 616, an SCP 644 and aVLR 656 are provided. SCP 644 includes an AC 646 and an HLR 652. Aserving MSC 658 is located in roaming area 616. In FIG. 7, although MSCsare shown as separate entities from the HLR and VLR in the respectiveareas, in a real application the HLR/VLR functions may be integratedwith the MSCs.

In this example, when the subscriber enters roaming area 616, hiscellular phone sends a registration request containing its MIN (MobileID number) to serving MSC 658, as illustrated at step 657. At step 659,serving MSC 658 sends an authentication request (AUTHRQST) message toits VLR 656 to authenticate the cellular phone. VLR 656 in turn sendsthe request to the subscriber's home HLR 636 in home area 612 at step660, based on the subscriber's MIN. HLR 636 in turn sends the request toAC 632 at step 691. AC 632 then performs authentication processing andsends authrqst response to HLR 636 at step 692, indicating whether thecellular phone is authenticated. HLR 636 in turn sends the authrqstresponse to VLR 656 at step 661. Assuming the cellular phone isauthenticated, VLR 656 so informs serving MSC 658 at step 662. Then,serving MSC 658 sends a registration notification (REGNOT) message toits VLR 656 at step 663. The REGNOT message contains the MSCID ofserving MSC 658. VLR 656 in turn sends the REGNOT message to HLR 636 inhome area 612 at step 664. Upon receiving the REGNOT message, HLR 636updates the information in the VLR₋₋ MSCID field of the subscriber'sprofile record in the SUBS file to show new serving MSC 658 and VLR 656.

Moreover, the fraud protection mediation module of HLR 636 uses theMSCID included in the REGNOT message to access the MPCM file record ofserving MSC 658 to determine, from the OPT7₋₋ IND field, whether thearea MSC 658 serves supports AC processing and from the OPT12₋₋ INDfield, whether MSC 658 is fraud capable. The mediation module also usesthe MIN of the subscriber's cellular phone included in the REGNOTmessage to access the subscriber's profile record in the SUBS file todetermine, from the AUTH₋₋ ENABLED field, whether the subscriber has anactive authentication and from the FRAUD₋₋ INFO field, whether thesubscriber has fraud protection authorized. The mediation module furtherreads the SYSP file of HLR 636 to determine whether the BYPASS₋₋ FPfield is activated. Then, the mediation module refers to the AC/FPlookup table in HLR 636 to determine whether an AC check, an FP check,or both should be performed on the subscriber's cellular phone. Afterhaving determined the appropriate check or checks that are needed, themediation module sends an appropriate request to the conventionalcomponents of HLR 636 to perform the check or checks on the subscriber'scellular phone.

Then, HLR 636 sends a regnot response back to VLR 656 at step 665, whichcontains relevant parts of the subscriber's profile record from the SUBSfile of HLR 636. VLR 656 stores the subscriber's profile in its databaseand sends the regnot response to serving MSC 658 with the relevant partsof the subscriber's profile at step 666. After step 666, the roamingsubscriber is registered in this new roaming area.

When a calling party places a call to this roaming subscriber (alsoreferred to as "receiving party"), as illustrated in FIG. 7, a callorigination and the dialed digits are received by home MSC 643 at step667. MSC 643 is thus also referred to as originating MSC. Then, at step668, originating MSC 643 sends a location request (LOCREQ) message toHLR 636 in home area 612 of the receiving party. The LOCREQ messagecontains the dialed digits and other relevant information. Uponreceiving the dialed digits, HLR 636 accesses the SUBS file in the HLRusing the received dialed digits (which is typically the MIN of acellular phone) as the key to locate the receiving party's profilerecord to determine if the receiving party is a legitimate subscriber.

If receiving party is a legitimate subscriber, then at step 669, HLR 636sends a routing address request (ROUTREQ) message to VLR 656 in roamingarea 616. The ROUTREQ message contains the MIN of the receiving party'scellular phone. VLR 656 then forwards the ROUTREQ message to serving MSC658 at step 670. In response to the ROUTREQ message, serving MSC 658consults its internal data structures to determine if it knows thereceiving party's cellular phone and whether the phone is alreadyengaged in a call on this MSC. Here, if the subscriber did not registerhis cellular phone with serving MSC 658 initially, i.e., if step 657 tostep 666 have not been performed on the receiving party's cellular phoneat the time a call origination is received, then serving MSC 658 wouldnot recognize the receiving party's cellular phone. In such a case, step672 to step 680 as outlined in box A will be performed. In such case,serving MSC 658 may obtain the receiving party's profile from its VLR656 by sending it a qualification request (QUALREQ) message at step 672.If the cellular phone is also unknown to VLR 656 or if the informationrequested is not available at VLR 656, VLR 656 sends the QUALREQ messageto HLR 636 in home area 612 at step 674. The QUALREQ message typicallycontains the MSCID of serving MSC 658. Upon receiving the QUALREQmessage by HLR 636, the fraud protection mediation module of HLR 636uses the MSCID included in the QUALREQ message to access the MPCM filerecord of serving MSC 658 to determine, from the OPT7₋₋ IND field,whether the area MSC 658 serves supports AC processing and from theOPT12₋₋ IND field, whether serving MSC 658 is fraud capable. If theQUALREQ is received without an MSCID, HLR 636 will read the SPCD file inthe HLR to obtain the default MSCID for serving MSC 658. The mediationmodule also uses the MIN of the receiving party cellular phone includedin the AUTHRQST message to access the receiving party's profile recordin the SUBS file to determine, from the AUTH₋₋ ENABLED field, if thesubscriber has an active authentication. The mediation module furtherreads the SYSP file of HLR 636 to determine if the BYPASS₋₋ FP isactivated. Then, the mediation module refers to the AC/FP lookup tablein HLR 636 to determine whether an AC check, an FP check, or both shouldbe performed on the receiving party's cellular phone. After havingdetermined the appropriate check or checks that are needed, themediation module sends a request to the conventional components of theHLR 636 to perform the check or checks on the receiving party's cellularphone. Then, HLR 636 sends a qualreq response to VLR 656 at step 678.The qualreq response contains relevant information about the receivingparty's profile. VLR 656 in turn sends the qualreq response to servingMSC 658 at step 680. Upon receiving the qualreq response, if thereceiving party's cellular is idle, serving MSC 658 allocates atemporary identifier TLDN (Temporary Local Directory Number) and returnsthis information to VLR 656 in the routreq message at step 682. VLR 656in turn sends the routreq message to HLR 636 at step 684. When theroutreq message is received by HLR 636, it returns a locreq response tooriginating MSC 643 at step 686. The locreq response includes routinginformation which includes the MSCID of serving MSC 658 and the TLDN.Finally, originating MSC 643 establishes a voice path to serving MSC 658using existing interconnection protocols (e.g., SS7) and the routinginformation specified in the locreq response, as illustrated at step688. In this way, an FP check may be used as a backup protection.Alternatively, a cellular carrier may have the HLR bypass the FP checkin areas that support AC processing to provide convenience to thesubscribers so that they do not have to enter their PINs to unlock thatcellular phones.

FIG. 8 shows a flow chart illustrating the operation of fraud protectionmediation module 228. The steps in FIG. 8 are performed by HLR 636 ofFIG. 7 although other HLRs are capable of performing these steps. Themediation module implements fraud protection mediation in any of thefollowing situations: (1) a registration notice (REGNOT) is received bythe HLR from an MSC currently serving a subscriber's cellular phone; (2)a qualification request is received by the HLR from a serving MSC forobtaining a subscriber's profile; and (3) the HLR sends a qualificationdirective to a serving MSC, with the updated or modified profile of thesubscriber.

In any one of above three situations, the mediation module first readsthe MPCM file record of the serving MSC using the MSCID received in theregistration notification (REGNOT) message or a qualification request(QUALREQ), for example. If an incoming QUALREQ is received without anMSCID, the HLR will read the SPCD file in the HLR to obtain the defaultMSCID. From the OPT7₋₋ IND field of the MPCM file record, the mediationmodule determines whether this serving MSC is fraud capable; and fromthe OPT12₋₋ IND field of the MPCM file record, the mediation moduledetermines whether the area this serving MSC serves supports ACprocessing, as illustrated by step 860. Then, at step 862, the mediationmodule reads the SUBS file using the subscriber's MIN as key to locatethe subscriber's profile record. From the profile record, the mediationmodule determines whether the subscriber has an active authenticationand whether the subscriber has fraud protection authorized, from theAUTH₋₋ ENABLED field and the FRAUD₋₋ INFO field respectively.

Next, at step 864, the mediation module reads the SYSP file to determineif the fraud protection bypass feature is activated for the HLR. Basedon the information retrieved from the various files, the mediationmodule reads the AC/FP lookup table to determine which case is present,at step 868. The mediation module determines whether an AC check shouldbe performed, based on the isac field in the lookup table, at step 870.If so, the mediation module sends an AC check request to theAuthentication Center connected to the HLR to initiate an AC check onthe subscriber's cellular phone. Then, the mediation module determinesif an FP check should be performed based on the fp field in the lookuptable, at step 874. If an AC check is not to be performed, step 872 isbypassed. If the mediation module determines that an FP check should beperformed on the subscriber's cellular phone, it sends a fraudprotection check request to the conventional components of the HLR toinitiate an FP check on this subscriber's cellular phone. If, however,the FP check is not required, the mediation module bypasses step 876 andexits at step 878.

Therefore, by using the improved HLR of the invention, fraud protectionprocessing can be performed as a backup protection. Alternatively, acellular carrier may have the HLR bypass the fraud protection processingin areas that support AC processing to provide convenience to thesubscribers so that PINs are not required for using the cellular phones.In any case, the cellular phones are still protected against fraud.

While the invention has been described in conjunction with specificembodiments, it is evident that many alternatives, modifications andvariations will be apparent to those skilled in the art in light of theforegoing description. Accordingly, it is intended to embrace all suchalternatives, modifications and variations as fall within the spirit andscope of the appended claims.

What is claimed is:
 1. A method of providing fraud protection mediationimplemented by a home location register (HLR) for a mobile telephonesystem, the method comprising the steps of:(a) determining ifauthentication processing is supported by a subscriber's cellular phone,comprising the steps of:(a1) determining whether an area the subscriberis in supports authentication processing by accessing, in the HLR, aMobile Switching Center ID Point Code Map (MPCM) file record associatedwith a Mobile Switching Center (MSC) to determine whether the MSCsupports the authentication processing, and (a2) determining whether thesubscriber has an active authentication by accessing a profile record ofthe subscriber in a SUBS file of the HLR; (b) determining if fraudprotection processing is supported by the subscriber's cellular phone,comprising the steps of:(b1) determining whether the MSC supports thefraud protection processing by accessing the MPCM file record associatedwith the MSC, and (b2) determining whether the subscriber has fraudprotection authorized by accessing the profile record of the subscriber;(c) determining whether fraud protection processing is bypassed for theHLR; (d) performing an authentication check on the subscriber's cellularphone if the authentication processing can be performed on thesubscriber's cellular phone; and (e) if the authentication check is notperformed, performing a fraud protection check on the subscriber'scellular phone if the fraud protection processing can be performed onthe subscriber's cellular phone.
 2. The method of claim 1 furthercomprising the step of:(f) if the authentication check is performed onthe subscriber's cellular phone, performing a fraud protection check onthe subscriber's cellular phone if the fraud protection processing canbe performed on the subscriber's cellular phone and the fraud protectionprocessing is not bypassed for the HLR.
 3. The method of claim 2,whereinstep (a) includes the steps of:(a1) determining whether an area thesubscriber is in supports authentication processing, and (a2)determining whether the subscriber has an active authentication; andwherein step (b) includes the steps of:(b1) determining whether an MSCcurrently serving the subscriber's cellular phone supports the fraudprotection processing, and (b2) determining whether the subscriber hasfraud protection authorized.
 4. A home location register (HLR) forproviding fraud protection mediation in a mobile telephone system,comprising:a first portion configured to determine if authenticationprocessing is supported by a subscriber's cellular phone, wherein thefirst portion includes:a first subportion configured to determinewhether an area the subscriber is in supports authentication processing,and a second subportion configured to determine whether the subscriberhas an active authentication; a second portion configured to determineif fraud protection processing is supported by the subscriber's cellularphone, wherein the second portion includesa first part configured todetermine whether a Mobile Switching Center (MSC) currently serving thesubscriber's cellular phone supports the fraud protection processing,and a second part configured to determine whether the subscriber hasfraud protection authorized; a third portion configured to determinewhether fraud protection processing is bypassed for the HLR; a fourthportion configured to perform an authentication check on thesubscriber's cellular phone if the authentication processing can beperformed on the subscriber's cellular phone; a fifth portion configuredto perform a fraud protection check on the subscriber's cellular phoneif the authentication check is not performed and the fraud protectionprocessing can be performed on the subscriber's cellular phone; and asixth portion configured to store a Mobile Switching Center ID PointCode Map (MPCM) file containing individual MSCs' file records and a SUBSfile containing individual subscribers' profile records, wherein thefirst subportion of the first portion includes a component configured toaccess the MPCM file record associated with the MSC to determine whetherthe MSC supports the authentication processing; wherein the secondsubportion of the first portion includes a component configured toaccess a profile record of the subscriber in the SUBS file to determinewhether the subscriber has an active authentication; wherein the firstpart of the second portion includes a component configured to access theMPCM file record associated with the MSC to determine whether the MSCsupports the fraud protection processing; and wherein the second part ofthe second portion includes a component configured to access the profilerecord of the subscriber to determine whether the subscriber has fraudprotection authorized.
 5. The HLR of claim 4 further comprising:aseventh portion configured to perform a fraud protection check on thesubscriber's cellular phone if the authentication check is performed onthe subscriber's cellular phone, the fraud protection processing can beperformed on the subscriber's cellular phone and the fraud protectionprocessing is not bypassed for the HLR.
 6. The HLR of claim 5,whereinthe first portion includes:a first subportion configured to determinewhether an area the subscriber is in supports authentication processing,and a second subportion configured to determine whether the subscriberhas an active authentication; and wherein the second portion includes:afirst part configured to determine whether an MSC currently serving thesubscriber's cellular phone supports the fraud protection processing,and a second part configured to determine whether the subscriber hasfraud protection authorized.